Entry and Ventilation

COURSE: FIREFIGHTER PRE-BASIC SESSION REFERENCE: 7 TOPIC: ENTRY AND VENTILATION TIME REQUIRED: THREE HOURS MATERIALS: ACQUIRED STRUCTURE OR FORCIBLE ENTRY PROPS, VARIOUS HAND AND POWER TOOLS REFERENCES: ESSENTIALS OF FIRE...


          3) Remove all splinters of glass before going through

      c. Position ladders upwind from windows

      d. When time and/or fire does not permit use of tool, knock out window with ladder

      e. Glass panes may be replaced with unbreakable plastic panes

          1) May be cut with power saw

          2) With other than steel frame, knock out entire window frame

          3) May have knock out panel which can be removed by striking corner with pick of axe

  2. Casement windows

       a. Window hinged vertically with moving part of window attached to crank

           1) Window crank usually light

           2) Window lock located in middle or bottom of window

      b. Best way to open window is break out pane of glass, reach in and unlock window, and force it

          open with pry tool

      c. If heat not intense, remove second pane to operate crank

      d. Many casement windows too narrow to allow entry

      e. Narrow windows often located at sides of large glass picture window

III. INTRODUCTION TO VENTILATION (7-3)

A. Ventilation Techniques and Theory

  1. Hot air rises using the path of least resistance and spreads or mushrooms out and downward

  2. Natural ventilation utilizes existing opening such as windows and roof openings

  3. Mechanical ventilation utilizes smoke ejectors or blowers

  4. Hydraulic ventilation utilizes nozzles and water flow air currents

B. Importance and Timing of Ventilation

  1. Coordinate with fire attack since the increase in air flow will accelerate burning

  2. Ventilation removes smoke and heat and increases visibility

C. Ventilation Equipment

  1. Smoke ejector - electric or gas-powered fan designed to exhaust smoke or blow in fresh air; air

      blows over motor; generally placed high in opening to exhaust smoke or low in opening to

      introduce fresh air

  2. Blower - electric or gas-powered fan designed to force air into an area at high velocity; placed six

      to ten feet from opening with air cone covering as much of the opening as possible

  3. Nozzle - nozzle is positioned two to three feet from opening with stream covering as much of

      opening as possible (at least 90%)

D. Backdraft

  1. A condition where there is insufficient air to support combustion

  2. A sudden introduction of fresh into an oxygen-starved fire causes a backdraft explosion

  3. Signs of backdraft include puffing smoke going in and out of the building, dark smoke in the

      structure with little flame, smoke emitting from openings in building

  4. Backdraft is relieved by venting at the highest point in the structure

E. Roof Construction

  1. Shingle - consists of plywood sheathing on roof trusses, tar paper, and asphalt shingles

  2. Composition - consists of wood or metal sheathing covered with felt material; tar and gravel

       provides water resistance

IV. VENTILATION TECHNIQUES (7-4)

A. Windows

  1. When time permits, windows should be opened

       a. Double hung windows should be opened two-thirds down from the top and one-third up from

           the bottom

       b. Open other types of windows as much as possible

       c. Storm windows must also be opened or removed

       d. Shades, blinds, drapes, curtains, and other window coverings must be moved away or removed

       e. When wind is a factor, windows on leeward side should be opened first

  2. Window and roof ventilation

       a. When roof or roof features must be opened for venting, windows on top floor should be

           opened

       b. If windows on several floors must be opened, begin on top and work down

       c. Opening windows from below first may cause fire and smoke spread

B. Natural Roof Openings

  1. In multi-story buildings, vertical shafts carry stairways, elevators, dumbwaiters, electric wiring,

      heating ducts, and plumbing and sewer pipes

  2. Shafts extend full height of building